some general questions regarding freebsd on rasp pi

[Paul Mather]

On Sep 3, 2015, at 10:16 AM, John <freebsd-lists at potato.growveg.org> wrote:

> On Wed, Sep 02, 2015 at 02:49:31PM +0100, John wrote:
> 
>> Just need to update ports and start building what I need. One answer i've not been able
>> to find - is it easy to clock the pi under freebsd? Looking for 1GHz 
>> (think the ram is half this)
> 
> in the grand tradition of answering myself, the way to do this with the rasp 2
> 
> hw.cpufreq.turbo=1
> dev.cpu.0.freq=900
> 
> in /etc/sysctl.conf and reboot, or modify them directly. Now i have:
> 
> # sysctl hw.cpufreq
> hw.cpufreq.temperature: 43312
> hw.cpufreq.voltage_sdram_p: 1200000
> hw.cpufreq.voltage_sdram_i: 1200000
> hw.cpufreq.voltage_sdram_c: 1200000
> hw.cpufreq.voltage_core: 1312500
> hw.cpufreq.turbo: 1
> hw.cpufreq.sdram_freq: 450000000
> hw.cpufreq.core_freq: 250000000
> hw.cpufreq.arm_freq: 900000000
> 
> and
> 
> # sysctl dev.cpu
> dev.cpu.3.%parent: cpulist0
> dev.cpu.3.%pnpinfo: name=cpu at 3 compat=arm,cortex-a7
> dev.cpu.3.%location: 
> dev.cpu.3.%driver: cpu
> dev.cpu.3.%desc: Open Firmware CPU
> dev.cpu.2.%parent: cpulist0
> dev.cpu.2.%pnpinfo: name=cpu at 2 compat=arm,cortex-a7
> dev.cpu.2.%location: 
> dev.cpu.2.%driver: cpu
> dev.cpu.2.%desc: Open Firmware CPU
> dev.cpu.1.%parent: cpulist0
> dev.cpu.1.%pnpinfo: name=cpu at 1 compat=arm,cortex-a7
> dev.cpu.1.%location: 
> dev.cpu.1.%driver: cpu
> dev.cpu.1.%desc: Open Firmware CPU
> dev.cpu.0.temperature: 42.2C
> dev.cpu.0.freq_levels: 900/-1 600/-1
> dev.cpu.0.freq: 900
> dev.cpu.0.%parent: cpulist0
> dev.cpu.0.%pnpinfo: name=cpu at 0 compat=arm,cortex-a7
> dev.cpu.0.%location: 
> dev.cpu.0.%driver: cpu
> dev.cpu.0.%desc: Open Firmware CPU
> dev.cpu.%parent:


FWIW, I believe that powerd is supported on the Raspberry Pi 2, so if you add powerd_enable="YES" to your /etc/rc.conf it will switch between the two CPU frequencies depending upon CPU load.

Cheers,

Paul.